Method for accelerating terminal of wireless communication system accessing network

ABSTRACT

A method for accelerating network accessing of a terminal in a wireless communication system, comprises: a wireless terminal receiving system parameter information, and after obtaining system information of a base station identifier (BS ID) and a network access provider identifier (NAP ID), immediately judging validity of the NAP ID, or validity of both the NAP ID and the BS ID; if a result of the judgment is “valid”, the terminal proceeding to a subsequent procedure of the network discovery and selection according to information stored in the terminal, otherwise, carrying out a new procedure of network discovery and selection. The method avoids continuing to perform processes such as message receiving and decoding in the case that a NAP ID or a BS ID is invalid according to a procedure in the current protocol, thereby increasing the speed of network accessing of a terminal.

RELATED APPLICATION DATA

This application claims priority and benefit of PCT/CN2007/003921, filedDec. 29, 2007, which claims priority from Chinese patent application no.200710143444.0, filed Jul. 31, 2007, the entire contents of which arehereby incorporated by reference.

TECHNICAL FIELD

The present invention relates to an access network technique in awireless communication system, and in particular, to a method for awireless communication terminal to access a network.

BACKGROUND OF THE INVENTION

In current wireless networks, there are both operators of accessnetworks and those of service networks, and an access network can beshared by a plurality of service networks and a geographical districtcan also be provided with services by a plurality of operators of accessnetworks. In such a complex operating mode, functions for discoveringand selecting a network become more and more important.

In current wireless communication networks, schemes for implementingnetwork discovery and selection have their own characteristics, but inall these schemes, it is firstly required to acquire an identifier of anetwork, and then a terminal performs subsequent processing according toinformation stored in it.

Taking a WiMAX system as an example, in its newly released version ofNWG1.1.0, a procedure and method for a WiMAX terminal to discover andselect a network are described. Wherein, a procedure for discovering andselecting a network in the case that a terminal stores the configurationinformation generated when performing a relevant subscription isdescribed. In this case, the base station can optimize the process ofaccessing the network, including discovering and selecting the network,by using the stored configuration information generated whensubscribing. From this version, it can be seen that the currentprocedure of network discovery and selection as well as accessing basedon “information on the last connection” or “configuration informationgenerated when subscribing” comprises the following procedure sequences:

In the case based on “information on the last connection”, a terminalperforms a procedure of judging validity of the last download channeldescriptor (DCD) count value prior to a procedure of judging validity ofa network access provider ID (NAP ID) and a base station ID (BS ID). Andif it judges that the DCD count value is invalid, the terminal continuesto acquire messages such as a DCD message.

In the case based on “configuration information generated whensubscribing”, a terminal directly acquires messages such as a DCDmessage and then performs a procedure of judging validity of a NAP ID.

According to the IEEE802.16e-2005 protocol, a downlink mapping (DL-MAP)message includes a “DCD count value” and a “BS ID (including a NAP ID)”,and a DCD message (a message sent by a BS periodically, definingcharacteristics of a downlink physical channel) includes a“configuration change count” and a “network service provider ID (NSP ID)change count value”.

According to the IEEE802.16e-2005 protocol, in downlink synchronization,a terminal always receives a DL-MAP message first to obtain a “DCD countvalue” and a “BS ID (including NAP ID)”, and then receives controlmessages such as a DCD message.

Therefore, it can be seen from the above analysis that according to theprocedure in current protocols, although the terminal decodes a DL-MAPmessage first to obtain a “BS ID”, a “NAP ID” and a “DCD count value”,it does not judge validity of the “NAP ID” and “BS ID”, leading to aresult that even if the “NAP ID” or “BS ID” decoded from the DL-MAP isinvalid, the terminal will still perform a subsequent procedure ofobtaining messages such as a DCD message, thus increasing the time takenfor a terminal to discover and select a network, and hence affecting thespeed of network accessing of the terminal.

SUMMARY OF THE INVENTION

The technical problem to be solved in the present application is toprovide a method for accelerating network accessing of a terminal in awireless communication system in order to improve the existing procedureunder the current protocol, reduce the time taken for a terminal todiscover and select a network, and thereby increase the speed of networkaccessing of the terminal.

In order to solve the above technical problem, the present inventionprovides a method for accelerating network accessing of a terminal in awireless communication system, comprising steps of:

(a) a wireless terminal receiving system parameter information, andafter obtaining system information of a base station identifier (BS ID)and a network access provider identifier (NAP ID), immediately judgingvalidity of the NAP ID, or validity of both the NAP ID and the BS ID;

(b) if a result of the judgment is “valid”, the terminal proceeding to asubsequent procedure of the network discovery and selection according toinformation stored in the terminal; otherwise, carrying out a newprocedure of network discovery and selection.

Furthermore,

if the terminal stores information on previous connections, then in thestep (a), the terminal judges validity of both the NAP ID and the BS ID;

if the terminal stores configuration information generated whensubscribing, then in the step (a), the terminal judges validity of theNAP ID.

Furthermore, the subsequent procedure in the step (b) comprisesreceiving, parsing and processing physical channel parameter messages.

Furthermore, in the step (b), if a result of the judgment is “invalid”,then the terminal starts a new procedure of network discovery andselection, instead of receiving, parsing and processing physical channelparameter messages according to a current protocol.

Furthermore, in the step (a), the terminal obtains the BS ID and the NAPID as well as a download channel descriptor (DCD) count value bysynchronizing a downlink channel and parsing a downlink mapping (DL-MAP)message.

Furthermore, in the step (a), the terminal stores information onprevious connections and the subsequent procedure in the step (b)comprises steps of:

(b1) judging whether the DCD count value matches up with a DCD countvalue stored in the terminal; if yes, ending the network discovery andselection process, otherwise, proceeding to step (b2);

(b2) receiving, parsing and processing a DCD message and an uploadchannel descriptor (UCD) message as well as a network service provideridentifier (NSP ID) change count value, and proceeding to a subsequentprocedure according to a protocol.

Furthermore, in the step (a), the terminal stores configurationinformation generated when subscribing, and the subsequent procedure inthe step (b) comprises:

receiving, parsing and processing a download channel descriptor (DCD)message and an upload channel descriptor (UCD) message as well as anetwork service provider (NSP) change count value, and proceeding to asubsequent procedure according to a protocol.

In the present invention, in a network discovery and selection procedurebased on “pre-existing connection information”, after a BS ID and a NAPID are obtained through reception of information of a wirelesscommunication system, validity of the BS ID and the NAP ID is judgedfirst, and then a subsequent procedure is performed; or in a networkdiscovery and selection procedure based on “pre-existing configurationinformation generated when subscribing”, validity of the NAP ID isjudged first and then a subsequent procedure is performed, thus avoidingcontinuing to perform a series of useless procedures such as messagereceiving and decoding in the case that the NAP ID or the BS ID isinvalid according to the procedure in the current protocol, henceincreasing the speed of network accessing of a terminal.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an optimized procedure of network discovery and selectionbased on information on the last connection in a WiMAX network accordingto an embodiment of the present invention;

FIG. 2 is an optimized procedure of network discovery and selectionbased on configuration information generated when subscribing in a WiMAXnetwork according to an embodiment of the present invention.

PREFERRED EMBODIMENTS OF THE PRESENT INVENTION

The method for accelerating network accessing of a terminal in awireless communication system provided by the present inventioncomprises the following steps:

a wireless terminal receives system parameter information, and afterobtaining system information of a BS ID and a NAP ID, it immediatelyjudges validity of the NAP ID, or validity of both the BS ID and NAP ID;

if a result of the judgment is “valid”, the terminal proceeds to asubsequent procedure of receiving, parsing and processing physicalchannel parameter messages; otherwise, it carries out a new procedure ofnetwork discovery and selection.

In the above steps of the method, only if the NAP ID, or both the BS IDand the NAP ID are valid, the terminal continues to receive and processthe physical layer configuration messages, thus avoiding continuing toperform a process of receiving and processing physical layerconfiguration messages in the case that the NAP ID or BS ID is invalid,thereby accelerating the process of network discovery and selection bythe terminal.

The above technical scheme of the present invention will be described infurther detail in conjunction with specific embodiments and drawings.

In embodiment 1, if a terminal stores information on previousconnections, the procedure of network discovery and selectionimplemented in this embodiment of the present invention is shown in FIG.1, comprising the following steps of:

Step 101: synchronizing a downlink channel, parsing a DL-MAP message,and respectively acquiring a NAP ID, a BS ID and a DCD count value;

Step 102: judging whether the NAP ID and BS ID match up with valuesstored in the terminal; if yes, proceeding to step 103, otherwiseturning to step 105;

Step 103: judging whether the DCD count value matches up with a valuestored in the terminal; if yes, proceeding to step 104, otherwise,turning to step 106;

Step 104: ending the network discovery and selection; Step 105:terminating a subsequent procedure in the original protocol andrestarting a process of network discovery and selection, i.e., theterminal does not have to receive, parse and process physical channelparameter messages according to the protocol;

Step 106: waiting and scanning to obtain DCD and upload channeldescriptor (UCD) messages and a NSP change count value, and proceedingto a subsequent procedure according to the protocol.

In embodiment 2, if a terminal stores configuration informationgenerated when subscribing, the procedure of network discovery andselection implemented in this embodiment of the present invention isshown in FIG. 2, comprising the following steps of:

Step 201: synchronizing a downlink channel, parsing a DL-MAP message,and respectively acquiring a NAP ID, a BS ID and a DCD count value;

Step 202: judging whether the NAP ID matches up with the configurationinformation generated when subscribing stored in the terminal; if yes,proceeding to step 203, otherwise turning to step 204;

Step 203: receiving physical layer configuration messages, such as DCDand UCD messages, as well as a NSP change count value, and proceeding toa subsequent procedure according to the protocol;

Step 204: terminating a subsequent procedure in the original protocol,and restarting a process of network discovery and selection.

Although the present invention is disclosed with reference to the abovepreferred embodiments, those embodiments are not meant to limit thepresent invention, and any person skill in the art can make somevariations and modifications without departing from the spirit and scopeof the present invention. Therefore, it is intended that the protectionscope of the present invention be limited by the claims appended hereto.

INDUSTRIAL APPLICABILITY

The present invention provides a method for accelerating networkaccessing of a terminal in a wireless communication system. In a networkdiscovery and selection procedure based on “pre-existing connectioninformation” or “pre-existing configuration information generated whensubscribing”, after a NAP ID and a BS ID are obtained through receptionof system information, validity of the NAP ID or validity of both theNAP ID and the BS ID is judged first, and then a subsequent procedure isperformed, thus avoiding continuing to perform a series of uselessprocedures such as message receiving and decoding in the case that theNAP ID or the BS ID is invalid according to the procedure in the currentprotocol, hence increasing the speed of network accessing of theterminal.

1. A method for accelerating network accessing of a wireless terminal ina wireless communication system, comprising steps of: (a) a wirelessterminal receiving system parameter information, and after obtainingsystem information of a base station identifier (BS ID) and a networkaccess provider identifier (NAP ID), immediately judging validity of theNAP ID, or validity of both the NAP ID and the BS ID; (b) if a result ofthe judgment is “valid”, the wireless terminal proceeding to asubsequent procedure of network discovery and selection according toinformation stored in the wireless terminal; otherwise, carrying out anew procedure of network discovery and selection.
 2. The methodaccording to claim 1, wherein: if the wireless terminal storesinformation on previous connections, then in the step (a), the wirelessterminal judges validity of both the NAP ID and the BS ID; if thewireless terminal stores configuration information generated whensubscribing, then in the step (a), the wireless terminal judges validityof the NAP ID.
 3. The method according to claim 2, wherein in the step(a), the wireless terminal stores configuration information generatedwhen subscribing, and the subsequent procedure in the step (b)comprises: receiving, parsing and processing a download channeldescriptor (DCD) message and an upload channel descriptor (UCD) messageas well as a network service provider (NSP) change count value, andproceeding to a subsequent procedure according to a protocol.
 4. Themethod according to claim 1, wherein the subsequent procedure in thestep (b) comprises receiving, parsing and processing physical channelparameter messages.
 5. The method according to claim 1, wherein in thestep (b), if a result of the judgment is “invalid”, then the wirelessterminal starts a new procedure of network discovery and selection,instead of receiving, parsing and processing physical channel parametermessages according to a current protocol.
 6. The method according toclaim 1, wherein in the step (a), the wireless terminal obtains the BSID and the NAP ID as well as a download channel descriptor (DCD) countvalue by synchronizing a downlink channel and parsing a downlink mapping(DL-MAP) message.
 7. A method according to claim 6, wherein in the step(a), the wireless terminal stores information on previous connectionsand the subsequent procedure in the step (b) comprises steps of: (b1)judging whether the DCD count value matches up with a DCD count valuestored in the wireless terminal; if yes, ending the network discoveryand selection, otherwise, proceeding to step (b2); (b2) receiving,parsing and processing a DCD message and an upload channel descriptor(UCD) message as well as a network service provider (NSP) change countvalue, and proceeding to a subsequent procedure according to a protocol.